A jetstream 4100 flies recommended airspeed behind a B767 but flies slower than recommended to keep ...

Attributes
ACN	405129
Time
Date	199806
Day	Fri
Local Time Of Day	1801 To 2400
Place
Locale Reference	airport : jfk
State Reference	NY
Altitude	agl bound lower : 1000 agl bound upper : 1000
Environment
Flight Conditions	VMC
Light	Daylight
Aircraft 1
Controlling Facilities	tower : jfk
Operator	common carrier : air carrier
Make Model Name	Jetstream 41
Operating Under FAR Part	Part 121
Navigation In Use	Other
Flight Phase	descent : approach
Route In Use	approach : visual
Flight Plan	IFR
Aircraft 2
Operator	common carrier : air carrier
Make Model Name	B767 Undifferentiated or Other Model
Operating Under FAR Part	Part 121
Navigation In Use	Other Other
Flight Phase	descent : approach landing other
Flight Plan	IFR
Person 1
Affiliation	company : air carrier
Function	flight crew : first officer
Qualification	pilot : commercial pilot : instrument pilot : cfi
Experience	flight time last 90 days : 250 flight time total : 3000 flight time type : 150
ASRS Report	405129
Person 2
Affiliation	company : air carrier
Function	flight crew : captain oversight : pic
Qualification	pilot : atp
Events
Anomaly	inflight encounter other non adherence : clearance other anomaly other anomaly other
Independent Detector	other flight crewa
Resolutory Action	none taken : anomaly accepted other
Consequence	Other
Supplementary
Primary Problem	ATC Human Performance
Air Traffic Incident	other
Situations
Airport	procedure or policy : unspecified

Narrative:

15 mi out we were told to follow a B767 to an ILS to runway 22L. We had the B767 in sight right away and TCASII range showed 6 mi which was in agreement with what approach told us. On localizer and 10 mi out, the B767 and we were given 180 KTS to the marker. We were holding 180 KTS and I noticed the TCASII range was closing. At an estimated 5 mi range I began to slow to attempt to hold 6 mi at 165 KIAS. Approach said to keep our speed up as we had another heavy jet 4 mi behind us. The range with the B767 ahead stayed steady and I held my speed. As the GS came in, I stayed 1 DOT high and started to descend. At 1000 ft AGL we hit the wake and the aircraft rolled 30 degrees left, then right 30 degrees. I recovered wings level, added power and went 1 1/2 DOT high on GS. At 800 ft AGL we hit the wake again with the same results. The B767 was high on the approach all the way in and touched down 1000 ft past the aiming point. I also landed long to avoid the wake. Meanwhile we had received several calls from approach and tower to keep our speed up! As we touched down before the nose even came down, tower began giving taxi instructions! Funny, I never heard them do that to the military jets! One level of safety, my ass! Jfk being our home base, we try our best to cooperate, ie, 250 KTS to 5 mi or 150 KTS at 15 mi. I'd say that's pretty flexible, eh? But lately we've been getting taken advantage of. Maybe those approach and tower guys should be required to ride along a turboprop commuter to get a good idea of the crap that we get told to do sometimes. Callback conversation with reporter revealed the following information: reporter participated in wake turbulence structured callback program. Reporter had a fear of encountering the wake from the B767 so he flew the airspeed that kept the separation distance constant. The B767 evidently flew high on the GS just as the reporter did and reporter encountered wake regardless of distance in trail.

Original NASA ASRS Text

Title: A JETSTREAM 4100 FLIES RECOMMENDED AIRSPD BEHIND A B767 BUT FLIES SLOWER THAN RECOMMENDED TO KEEP DISTANCE FROM PRECEDING HVY AS IT SLOWS DOWN. JETSTREAM EVENTUALLY HAS A WAKE TURB ENCOUNTER AT JFK.

Narrative: 15 MI OUT WE WERE TOLD TO FOLLOW A B767 TO AN ILS TO RWY 22L. WE HAD THE B767 IN SIGHT RIGHT AWAY AND TCASII RANGE SHOWED 6 MI WHICH WAS IN AGREEMENT WITH WHAT APCH TOLD US. ON LOC AND 10 MI OUT, THE B767 AND WE WERE GIVEN 180 KTS TO THE MARKER. WE WERE HOLDING 180 KTS AND I NOTICED THE TCASII RANGE WAS CLOSING. AT AN ESTIMATED 5 MI RANGE I BEGAN TO SLOW TO ATTEMPT TO HOLD 6 MI AT 165 KIAS. APCH SAID TO KEEP OUR SPD UP AS WE HAD ANOTHER HVY JET 4 MI BEHIND US. THE RANGE WITH THE B767 AHEAD STAYED STEADY AND I HELD MY SPD. AS THE GS CAME IN, I STAYED 1 DOT HIGH AND STARTED TO DSND. AT 1000 FT AGL WE HIT THE WAKE AND THE ACFT ROLLED 30 DEGS L, THEN R 30 DEGS. I RECOVERED WINGS LEVEL, ADDED PWR AND WENT 1 1/2 DOT HIGH ON GS. AT 800 FT AGL WE HIT THE WAKE AGAIN WITH THE SAME RESULTS. THE B767 WAS HIGH ON THE APCH ALL THE WAY IN AND TOUCHED DOWN 1000 FT PAST THE AIMING POINT. I ALSO LANDED LONG TO AVOID THE WAKE. MEANWHILE WE HAD RECEIVED SEVERAL CALLS FROM APCH AND TWR TO KEEP OUR SPD UP! AS WE TOUCHED DOWN BEFORE THE NOSE EVEN CAME DOWN, TWR BEGAN GIVING TAXI INSTRUCTIONS! FUNNY, I NEVER HEARD THEM DO THAT TO THE MIL JETS! ONE LEVEL OF SAFETY, MY ASS! JFK BEING OUR HOME BASE, WE TRY OUR BEST TO COOPERATE, IE, 250 KTS TO 5 MI OR 150 KTS AT 15 MI. I'D SAY THAT'S PRETTY FLEXIBLE, EH? BUT LATELY WE'VE BEEN GETTING TAKEN ADVANTAGE OF. MAYBE THOSE APCH AND TWR GUYS SHOULD BE REQUIRED TO RIDE ALONG A TURBOPROP COMMUTER TO GET A GOOD IDEA OF THE CRAP THAT WE GET TOLD TO DO SOMETIMES. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR PARTICIPATED IN WAKE TURB STRUCTURED CALLBACK PROGRAM. RPTR HAD A FEAR OF ENCOUNTERING THE WAKE FROM THE B767 SO HE FLEW THE AIRSPD THAT KEPT THE SEPARATION DISTANCE CONSTANT. THE B767 EVIDENTLY FLEW HIGH ON THE GS JUST AS THE RPTR DID AND RPTR ENCOUNTERED WAKE REGARDLESS OF DISTANCE IN TRAIL.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.

A jetstream 4100 flies recommended airspeed behind a B767 but flies slower than recommended to keep distance from preceding heavy as it slows down. Jetstream eventually has a wake turbulence encounter at jfk.